How Does Electric Field Strength Change with Distance from a Point Charge?

[pringless]

Suppose that the strength of the electric field about an isolated point charge has a certain value at a distance of 1 m. How will the electric field strength compare at a distance of 2 m from the point charge?

i think the field strength will be 1/4 at twice the distance. am i correct?

 

[Doc Al]

Originally posted by pringless
i think the field strength will be 1/4 at twice the distance. am i correct?

Right. The field from a point charge follows an inverse square law: $E = \frac{kq}{r^2}$

 

[M98Ranger]

Yes, you are correct. According to Coulomb's law, the electric field strength at a distance (r) from an isolated point charge is directly proportional to the magnitude of the charge (Q) and inversely proportional to the square of the distance (r^2). This means that as the distance from the point charge increases, the electric field strength decreases. In this case, since the distance is doubled from 1 m to 2 m, the electric field strength will decrease by a factor of 1/4, as you mentioned. This relationship is also known as the inverse square law and is a fundamental principle in electromagnetism.